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Modbus Dongle Pro Dds519Mr Modbus Register 18: Array rated pwr

Technical documentation for Modbus register 18 on Modbus Dongle Pro Dds519Mr. Data type: FP32. Includes Python and YAML configuration examples.

January 16, 2026 3 read

Technical Definition

The register array rated pwr at address 18 is used to monitor array rated pwr on the Modbus Dongle Pro Dds519Mr.

  • Protocol: Modbus RTU
  • Data Type: FP32
  • Unit: W
  • Access: Read Only

How to Read (Python pymodbus)

Use this code snippet to read this specific value via RS485:

from pymodbus.client.sync import ModbusSerialClient

client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB0', baudrate=9600)
client.connect()

# Read array_rated_pwr (Address: 18)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=18, count=2, unit=1)

if not result.isError():
    print(f"Raw Value: {result.registers}")
else:
    print("Error reading register")

client.close()

Integration (Home Assistant)

Paste this into your configuration.yaml:

- platform: modbus_controller
  name: "array_rated_pwr"
  address: 18
  value_type: FP32
  unit_of_measurement: "W"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Modbus Dongle Pro Dds519Mr]

    PLC -- "A+ (D+)" --> Device
    PLC -- "B- (D-)" --> Device
    PLC -- GND --> Device


💡 Engineer's Insight

Analysis: Rated power capacity in Watts (W) or Kilowatts (kW). Represents the maximum power the device is designed to handle.

Troubleshooting: Zero value could mean device is off, not rated for power, or a communication/configuration issue. Check device status and settings.